Field of the Invention and Related Art Statement
The present invention relates to a monitoring catheter for medical use which is inserted into and maintained in to the esophagus or stomach to effect drainage or measure temperature or pressure, thereby to observe, monitor and control postoperative progress or the progress after treatment.
Catheters for measuring temperature in the esophagus or stomach have been used heretofore. No problem arises merely when a temperature is measured with a catheter but if the catheter is kept inserted in the body cavity, secretions might be congested to require discharge of the secretions. Also when other items for diagnosis, e.g., measurement of pressure, are required, an exclusive drain tube, a tube for measuring pressure, etc. should be inserted and kept stuck independently, and such results in complicated and troublesome handling. Furthermore, a plurality of tubes must be inserted into the body cavities, which leads to increased pains given to a patient.
To solve these problems, there are known catheters having multiple functions as shown in Japanese Patent Application Laid-Open Nos. 51-84181, 56-139763, 60-85730, etc. These catheters are all used by maintaining them in the esophagus and have functions to measure a body temperature and at the same time, monitor the heart sound, lung sound or electrocardiogram. However, these catheters lack functions of draining body fluids and infusing a liquid drug, or monitoring pressure, etc. On the other hand, with the catheter described in Japanese Patent Application Laid-Open No. 60-99226, a body temperature can be measured and at the same time, body fluids can be drained and a liquid drug can be infused but a pressure cannot be measured. Furthermore, since any auxiliary conduit for sampling is not equipped, it is difficult to perform smooth drainage. Thus, the catheters in the prior art involve problems that when they are maintained in a cavity such as esophagus, etc., congestion of secretions occurs and the congested secretions should be drained, although there is no problem with these conventional catheters in the case of measuring a single item with each of these catheters.